1. Field of the Invention
The invention relates to an improved lock for a trailer and particularly a trailer lock that is easy for a latch bolt to insert and to perform locking or unlocking operations.
2. Description of the Prior Art
Travel and recreational activities have become increasingly popular these days. They not only benefit people""s physical and mental health, also are good to business and economic developments. During travels, many people use trailers to haul various outfits, foods, drinking water, etc. The trailer is usually fastened to the rear end of a car, and is anchored by a latch bolt. In order to guard the trailer against theft, a latch bolt doubles as a lock has been developed. FIGS. 9 through 11 show such a latch bolt. It mainly includes a lock member 60 with an insert hole 61 formed at one end for receiving a latch end 51 of a shank 50. The lock member 60 has another end formed an opening 62 to engage sequentially a latch member 90 and a lock core 80. The another end further has a groove 65 to engage with a cap 66. The lock core 80 has a key way 81 formed at one end, a pin hole 82 formed on one side to match an aperture 66 formed on the lock member 60 to receive a pin 64 to anchor the lock core 80 in the lock member 60, and a lock tongue 83 located at another end thereof to couple with a latch member 90. The lock core 80 may be turned and controlled by a key 70. The latch member 90 is integrally formed and includes a base plate 91 with a retain hole 911 formed thereon to match and couple with the lock tongue 83, a connection section 92 extended on one side, and an upper plate 93 connected to the connection section 92. The upper plate 93 has a latch frame 931 formed thereon.
When in use, the latch end 51 of the shank 50 is inserted into the latch member 90 through the insert hole 61 of the lock member 60. Then the key 70 is turned to turn the lock core 80 which turns the lock tongue 83 and drives the latch member 90 to turn. As a result, the direction of the latch frame 931 on the upper plate 93 changes. Then the latch frame 931 may latch the latch end 51 of the shank 50 to prevent the shank 50 from being pulled out of the lock member 60. This is a locked condition (as shown in FIGS. 12 and 13). On the other hand, the key 70 may be turned to drive the latch member 90 and change the direction of the latch frame 931 so that the shank 50 is not latched by latch frame 931. Then the shank 50 may be removed from the lock member 60 to form an unlocking condition. Insertion of the latch end is done at the opposite directions 180xc2x0 apart. Such a design has the following disadvantages:
1. As the latch end 51 and the insert hole 61 are aligned at positions of 180xc2x0 apart, there are only two inserting locations for the latch end of the shank 50. Operation is not convenient and is time-consuming.
2. The lock core has to be turned at a large angle of 180xc2x0 when in use. It is against the prevailing trend of locking devices that mostly adopt the turning angle of 90xc2x0. Such a design has no competitiveness and incurs higher cost.
In view of aforesaid disadvantages, the primary object of the invention is to provide an improved lock for a trailer that is easy for the latch bolt to be inserted to perform locking or unlocking operations, and is turned at a smaller angle (about 90xc2x0) when in use.
To attain the foregoing object, the invention mainly includes a latch bar and a lock member. The latch bar includes a latch bolt to match the key way, lock ring, connection shaft and lock core of the lock. Locking operations can be done easily. Unlocking can be accomplished by turning the lock core for a small angle and can be done quickly and conveniently.